QPQ (Quench Polish Quench) is a HEF Group trademarked process it’s a thermochemical treatment that enhances wear, fatigue, corrosion, appearance and friction properties of any ferrous material. Arcor PC® is a fully optimized version of QPQ only available through the TS global jobbing shop network.

These benefits result from the formation of an intermetallic compound (epsilom iron nitride) on the surface of the treated component, strengthened and supported by the diffusion of nitrogen.

Excellent black decorative appearance. Unlike electrolytic coatings, there is no hydrogen embrittlement with ARCOR

These steps entail the sequence:

  1. OXIDATION: 2-3 microns of the surface layer is transformed to an iron oxide. This is done by immersing the parts in specially formulated ‘salts’ between 400°C – 425°C (750°F -800°F).

  2. POLISHING: to improve surface finish

  3. RE-OXIDATION: to recover the oxide layer thickness that may have been lost during the polishing step. QPQ is prescribed when a smooth surface finish and maximum corrosion protection are required.

Treatment Parameters

Treating ferrous materials (steel, cast iron, stainless steel and Inconel alloys) at temperatures typically between 540°C and 580°C and treatment times between 30 and 210 minutes.


TSUK is home to the largest nitrocarburising baths in the UK, we can treat parts up to 1 metre in diameter and 3.2 metres in length.


Excellent black decorative appearance, lower & stabilise friction values.


Damper or Cylinder Rods, Axle Hinges, Crane Joint Plates, Electric Equipment Mechanisms, Automobile Lock Mechanisms, Hinge Pins, Operating Screws, Window Wiper Shafts, Balls For Bowling Games, Iron Industry Equipment, Etc.

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